Friday, July 8, 2011

Aqueduct Bridge over the Potomac: Yesterday and Today

My wife and I decided to take a walk along the Chesapeake & Ohio (C&O) Canal in Georgetown this past Memorial Day. Our little attempt at exercise gave me the perfect opportunity to check out the remains of the Aqueduct Bridge, which are located next to the canal path in the vicinity of present-day Key Bridge. Readers may recall that I have mentioned the Aqueduct Bridge in numerous posts over the past year. This bridge was one of three river crossings into Virginia from the D.C. side of the Potomac at the time of the Civil War.

The Aqueduct Bridge dates to the antebellum period, when Alexandria comprised part of the federal District of Columbia. Alexandria, a port city, desired to benefit from the trade that was moving along the C&O Canal to rival Georgetown. In 1830, a group of Virginia merchants formed the Alexandria Canal Company. They sought to extend the C&O Canal to the Virginia side of the Potomac River, and from there, to Alexandria. The Aqueduct Bridge, known as the Alexandria Aqueduct or Potomac Aqueduct, was designed to carry the canal across the river. Construction on the bridge and the Alexandria Canal began in the early 1830s and was completed in 1843. The bridge, an engineering marvel of the 19th century, cost a staggering sum of around one million dollars. With the extension of the C&O Canal to Cumberland, Maryland in 1850, the Aqueduct Bridge played a key role in bringing coal from western Maryland to the the port at Alexandria.

The Aqueduct Bridge featured prominently at the start of the Civil War. Virginia voters officially approved secession on May 23, 1861, and in the early morning hours of May 24, Union soldiers moved to occupy Alexandria and Arlington Heights. A Federal column including the 5th, 28th, and 69th New York crossed the Aqueduct Bridge into Virginia. Not long afterward, the Union Army constructed Forts Corcoran, Bennet, and Haggerty to guard the approaches to Aqueduct Bridge from the Virginia side of the river. These forts comprised part of what would become the ring of defenses built to protect Washington during the war.

The Aqueduct Bridge from the Washington side, with the C&O Canal in the foreground, ca. 1862-65 (courtesy of Library of Congress).

In his A Report on the Defenses of Washington to the Chief of Engineers, U.S. Army (1871), Brevet Major General John Gross Barnard noted that the Union military decided that a "permanent and secure bridge connecting Washington with the Virginia shore" was preferable to the use of the Aqueduct Bridge to transport military supplies to Alexandria by way of the canal. Some officers, as well as the canal company, initially objected to the suspension of canal operations across the Aqueduct Bridge. A "boat bridge" was contemplated for military purposes, but proved an unrealistic alternative given concerns about water depth, flooding, ice, and currents. Barnard described the subsequent transformation of the Aqueduct Bridge:

The tow-path of the aqueduct did indeed furnish a narrow passageway to horsemen and footmen; but this was far from adequate to the military exigencies. Accordingly, early in the winter of 1861-'62, the water was shut off from the aqueduct and its trough converted into a double-track wagonroad, the floor being overlaid with 4-inch planks and long inclines, on trestles, forming connections with the roads on either side.

Eventually three blockhouses and a rifle trench were placed at the Virginia end of the Aqueduct Bridge. The head of the bridge was also enclosed with a stockade to protect more effectively against cavalry raids. The Union Army contemplated placing a shore battery in Georgetown to command the length of the bridge, but decided against this defensive measure. A guard of one officer and thirty men usually covered each end of the Aqueduct Bridge.

One of the blockhouses near Aqueduct Bridge on the Virginia side (courtesy of Library of Congress).

Barnard, who oversaw the construction of the the defensive works around the nation's capital, concluded in his report that "the aqueduct served perfectly, throughout the entire period of the war, its new destination, and was recognized as an important and essential adjunct to the 'Defenses of Washington' and to the great military operations in Virginia."
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Looking at the top of the remains of the Aqueduct Bridge's Washington abutment along the C&O Canal. The canal entered here and crossed the Potomac. The Key Bridge dominates in the background. The office buildings of Rosslyn, Virginia are visible across the Potomac River.

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Another view of the Aqueduct Bridge during the Civil War (courtesy of Library of Congress). This photograph was taken from across the Potomac in Virginia. The Washington abutment is visible where the bridge hits the shore in Georgetown.

A side view of the Washington abutment. The arch to the left was expanded in 1889 to accommodate the Washington branch of the Baltimore & Ohio Railroad.

The bridge was returned to canal usage after the Civil War. In 1923, the Aqueduct Bridge was closed when the Key Bridge was built next door, and in 1933, the old bridge was largely dismantled. Today the remaining Washington abutment is a visible reminder of the existence of the Aqueduct Bridge and the place it occupied in the capital's Civil War history.

10 comments:

Fascinating post! I became interested in the Civil War Defenses of Washington D.C. while researching the letters of my great-great grandfather who was at Fort Lincoln, North of the Potomac from Dec. 1862-April 1864. I have visited most of the forts to the North and also Fort Ward. My interest is such that I have even made a presentation to my local CWRT group on the defenses. I'll be on vacation next week in Maryland and Virginia and hope to see some of the sites South of the Potomac and maybe check out the C&O Canal. I'm open to suggestions on this too.

Thanks, Greg. I recall you saying that you would be making a trip to the DC area this summer. The C&O Canal is an interesting place, so if you get to the District, you could walk along the towpath around Georgetown. If you get a chance, you also may want to visit Old Town Alexandria and see some of the Civil War-related sites down there. The city publishes a Civil War walking tour that may be available at Ft. Ward or the Visitor Center. In addition, Fairfax County has done a good deal on their website about Civil War sites in the county, from well-known to the more obscure.

Thanks Ron. I may just follow your suggestions. I have an extra day to explore the D.C. area and since I live in a major metropolitan area I prefer to stay out of big cities (ie. D.C. proper) and visit the less conjested areas when on vacation. Alexandria fills that bill. I will also be visiting Mount Vernon for the first time.

Fascinating information. I did not realize that the DC side of the abutment for the bridge is still in place. I just published an entry on Ft. Whipple/Ft. Myers during the Civil War, which was partially built to provide supporting fire for Ft. Corocoran, which in turn was supposed to help protect Aqueduct Bridge: http://civilwarwashingtondc1861-1865.blogspot.com/2011/07/ft-whippleft-myers.html

Thanks, Steven. I had noticed the abutment, but never knew what it was until relatively recently. Amazing how many such sites are tucked away around here.

Thanks for the link. There were indeed several forts that in essence supported the defense of Aqueduct Bridge, including Ft. CF Smith, which I wrote about a while ago. It seems that many of these were built in late 1861-63, once the Union Army got really serious about defending Washington.

Great article!! I am sitting here looking at your photo of the expanded arch done in 1889. I thought it was done around 1900 because my great great uncle worked on that expansion. In the photo I have of him you can clearly see the arch being worked on directly behind him. I am happy the arch is still there.

Thanks, Bill. Glad you liked the post. You may very well be right on the date. Although my source listed 1889, I see that the DC Inventory of Historic Sites says that the abutment was raised c. 1900-09. Great you have such a family connection!